Early stage melanoma: Lymphoscintigraphy, reproducibility of sentinel node detection, and effectiveness of the intraoperative gamma probe

PURPOSE: To assess the influence of lymphoscintigraphic and intraoperative gamma probe findings on the surgical management of melanoma and to test reproducibility of lymphoscintigraphic findings. MATERIALS AND METHODS: After lymphoscintigraphic identification of the sentinel node, intraoperative gamma probe localization and sentinel lymph node excision were performed in 25 patients. To assess reproducibility, 13 patients underwent lymphoscintigraphy twice within 2-17 days. A modified preparation of technetium-99m sulfur colloid with smaller particles than routinely obtained was injected intradermally around the lesion. Dynamic flow images were obtained at 10 seconds per frame followed by a series of static images obtained every 5 minutes for 30 minutes. RESULTS: A sentinel node was identified in all patients. In eight patients, multiple drainage pathways were seen and surgical management was changed. In 11 of the 13 who underwent lymphoscintigraphy twice, sentinel node identification was reproducible. CONCLUSION: Lymphoscintigraphy is reproducible in detection of the sentinel node and with the surgical probe helps effectively guide surgical management.